30th anniversary of the Sinclair ZX Spectrum

Chris Smith who runs the site zxdesign.info gavea quite technical talk on reverse engineering the Spectrum’sULA. This informationis available in the book: The ZX Spectrum ULA: How to Design aMicrocomputer. Chris alsogave some technical details on determining exactly how many machine cyclescould be executed between line refreshes and how this knowledge could be usedto overcome the ZX Spectrum’s 2 colour per 8x8 pixel block limit.

There was time for some of the attendees to talk about their memories of theSpectrum and things they’d done. One person had a Speccy2010 which is an FPGAimplementation of a Spectrum that can read data from SD card.

There were a couple of RaspberryPi‘s on show:one playing a short film and the other running a Spectrum emulator runningManic Miner which has to be one ofmy all-time favourite Spectrum games - I spent hours playing it and the sequelJet Set Willy when they werereleased. My son started playing the game and got hooked - I have a suspicionthat if I set up an emulator on the home PC he’d put as many hours in playingit as i did 29 years ago. Eben Upton of RaspberryPi fame also gave a shorttalk on how the Raspberry Pi came to be.

What I hadn’t expected is that people are still developing for the ZXSpectrum. Using emulators and PC-based development environments experiencedprogrammers are making use of the detailed knowledge of the machine that wasnot readily available (AFAIK) in the 1980s and still cranking out new gamessuch as Chris Smith’s isometric 3Dgame and Jason Railton’sBuzzsaw